PLEASE HELP WHICH ONES ARE PROPORTIONAL!!!!!!!!!!!??????????????
The formula to determine the diameter of a circle, d, is d=2r, where r is the radius. The radius of a circle is proportional to its diameter.

Nadia is baking muffins. Every 6 muffins require 1/3 cup of fruit. The number of muffins is proportional to the cups of fruit.

The volume of a cube is determined by the formula V=s3, where s is the side length. The volume of a cube is proportional to its side length.